Binaural sound localization depends on ear-level temporal and intensity encoding efficiency

Evidence

Lord Rayleigh (James William Strutt, 1843–1919) was strongly influenced by the work of Helmholtz. His book The Theory of Sound also discussed acoustic problems using mathematics. This work laid the groundwork for future study linking acoustics with perception. Rayleigh was also keenly interested in the ability to localize sounds in space. He proposed that two acoustic cues are used for sound localization: intensity differences and time differences across the ears. The intensity differences were produced by the presence of the head in the sound field, which can effectively block sound transmission. The time differences were produced by the differential travel times of sound across the ears. This theory, called the Duplex Theory of Sound Localization, has been validated numerous times (see Chapter 7). — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 70

Categorization

• DEFINE: Names the Duplex Theory of Sound Localization and its two cues: interaural intensity (head shadow) and interaural time differences.
• XREF: Connects to the reader’s broader interest in models of hearing; the two-cue duplex mechanism parallels the spectral/phase cue distinction familiar in visual psychophysics. — connects to: Normal hearing yields a temporal resolution factor near unity; Binaural microphones capture exact tympanum signals but depend on one’s own head shape; Cortical intensity encoding becomes ear-independent through strong interhemispheric connections (+6 more)
• corroborated: 2 independent passages support this claim — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 70

Broader Connections

• Head shading creates interaural level differences used for sound localization #exemplifies (0.90) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 726